German chemicals giant BASF has had its hostile $4.9bn (£2.8bn) takeover bid for rival firm Engelhard cleared by US competition authorities.
BASF is the world's largest chemicals company by sales
The firm also said it had extended the expiration date of its offer for Engelhard to 3 March, by which time it expects to have EU regulatory approval.
US-based Engelhard has repeatedly rejected BASF's $37 per share offer as too low.
BASF is the world's biggest chemicals firm with over 80,000 employees.
Engelhard is a leader in pollution-reducing catalytic converters for automotive and industrial use.
The company has hired investment bank Merrill Lynch as an adviser in the hope of finding a better offer than the one from BASF.
Last week Engelhard posted a 10% rise in net profit for the three months to the end of December, and said that more stringent emissions regulations across the world would help to drive continued sales growth.